Process of making refined sugar-cane wax



Patented Sept. 14, 1948 PROCESS OF MAKING aEFINEn, SUGAR-CANE wax oyal T. Balch, Roma, La"

Charles B. Broeg and R United States. of America assignors to the represented by the Secretary of Agriculture No Drawing. Application July 2, 1948,

' Serial No. 36,797

3 Claims. (01. 260-4285) (Granted under the act of mended April 30, 1928:

This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described, if patented in any country, may be manufactured and used by or for the Government of the United States of America for governmental purposes throughout the world without the payment to us of any royalty thereon.

This application is a continuation in part of our copending application for patent, SerialNo. 511,928, filed November 27, 1943, now abandoned.

This invention relates to waxes, and has among its objects the obtaining of light-colored hard wax products from the hard dark-colored wax products obtained from clarificatibn muds of sugarcane factories.

A process for the production of hard wax products from the crude waxproducts obtained from waste clarification muds of sugarcane factories is disclosed in U. S. Patent No. 2,381,420. The hard wax products obtained by the process of the patent are generally dark in color, which re-.

stricts their commercial uses. The general methods of decolorizing and bleaching waxes have no appreciable effect when applied to these wax products. However, we have i found a process whereby it is possible to obtain wax products of light color from these dark-colored wax products by a simple procedure.

Although the process of obtaining the hard dark-colored wax products, which are used as the raw material in the present invention, may be varied, it is preferable to obtain them according to the process of the above-mentioned patent, since the wax products thus obtained are purer than those obtained by the usual processes.

The process of the patent mentioned above in general comprises extraction of crude wax products from clarification muds, or other .waste products from sugarcanefactories, by means of an organic solvent for the wax products, preferably toluene, distilling off the solvent, and separation of the fatty portions from the residue thus obtained, leaving the hard dark-colored wax products, by means of a selective solvent for the fattyportions, preferably acetone.

We have found from a study of the hard darkcolored wax products so obtained that they contain a component in very substantial proportions that is very dark in color and is largely responsible for the dark color of the products. This component is compatible with the other wax components and the various components are mutually soluble in one another in a molten state, which may explain the ineffectiveness of March a, 1m. as :10 o. o. m)

the ordinary methods of decolorizing as applied to them. It was also found that certain solvents will dissolve the light-colored fractions, leaving a residue that is considerably more brittle and darker than. the original hard product. With certain other solvents which dissolve both fractions, the very dark-colored fraction can be forced from solution by the addition of water, or an organic liquid, which lowers the solubility of the solvent toward the wax products. These findings form the basis for the obtaining of wax products of light color and improved quality. ac-

f cording to the present invention.

A number of solvents will extract the light-colored fractions from the hard dark-colored wax products in a varying degree depending on the solvent used and the method employed. From a practical viewpoint, it is most desirable to use a solvent which will give the highest yield of light-colored fractions without including these fractions detrimental to the color or other properties of the extracted product. A maximum yield of the light-colored fractions insures light-colored final products of maximum hardness since there is high correlation between the lightness in color of the fraction and its hardness.

There is also another benefit derived by the application of the process of this invention. namely, a very large reduction in the ash content of the light-colored wax product as compared to the original wax products.

Wax products of varying hardness and of varying color may be obtained by fractionating the hard dark-colored wax products with different individual solvents or combinations of these so]- vents. The selection of a solvent for effecting the separation of the light and very dark-colored fractions is, therefore, a matter of prefer- 'ence, but regardless of the solvent used, the

same principles are involved.

A few of the preferable solvents are herein enumerated. Certain of the monohydric, saturated, aliphatic alcohols, especially those having not more than 3 carbon atoms, are very satisfactory. Those other than isopropanol are preferably used in their anhydrous state but with isopropanol a more effective separation of the lightfrom the dark-colored wax component is obtained when it is slightly diluted with water. Of these, isopropanol slightly diluted with water is preferred and claimed in the application of which this is a continuation in part because of its superior selective action upon the two fractions that it is desired to separate, and because the extraction may be conducted at a temperasolid phase.

tur which will liquefy the wax product, simply by refluxing a mixture of the wax product and alcohol at the boiling point of the alcohol.

Monohydric, saturated, aliphatic alcohols having more than 3 carbon atoms completely dissolve the hard dark-colored wax products, if anhydrous, but they can be employed if their solubility toward the wax products is reduced to a point where the very dark-colored fraction will not dissolve. This can be accomplished by the addition of water to the alcohol or of an organic liquid having low solubility toward the wax products. Such higher alcohols are not as satisfactory to use as isopropanol, however, because of their higher boiling points and lower evaporation rates.

Separation of the light-colored fractions from the very dark-colored fractions may also be effected with esters, particularly the acetic esters of monohydric, saturated, aliphatic alcohols, but their behavior and manner of use are similar to those of the alcohols having more than 3 carbon atoms. Thus they also require dilution with water.

Of the ketones, only acetone can be used without recourse to dilution with water or other liquid to reduce their solubility toward the waxes.

A specific procedure for carrying out the process of this invention is exhibited in the following detail explanation:

Mix the hard dark-coloredwax products, pref erably those obtained by separating'the fatty portions from the crude wax product according to the procedure indicated in the above-mentioned patent, with isopropanol suitably diluted and heat, preferably at the boiling point of the alcohol under a reflux condenser, for such a period that approximate solubility equilibrium is established.

No exact ratio of the hard dark-colored wax products to alcohol is required, but the wax extract is more easily handled if the concentration of wax product does not greatly exceed percent, since considerable cooling can then take place before crystallization of the wax product occurs to any great extent. After the reflux period, the insoluble fraction may be allowed to settle out and solidify and the solution containing the light-colored fraction decanted from the The insoluble residue may be retreated in a similar manner, if desired, to obtain maximum recovery of the desirable light-colored fraction.

The separate light-colored wax fraction may carry with it some chlorophyll and certain other pigments to a, minor extent which should be removed if wax of the lightest color is to be obtained. Treatment of the wax product in solution, or of the extracted light-colored wax product in a molten state, with the usual decolorizing materials will effect a satisfactory decolorization.

The light-colored fraction may be separated from the solution in any desired manner, but further improvement in the quality of the lightcolored wax product can be obtained by recrystallizingit from the alcohol or other solvent after the treatment with the decolorizing agent and filtering off the mother liquor, followed by freezing the crystallized wax product of the remaining solvent by distillation or evaporation.

The fraction of hard, very dark-colored we! product, which is insoluble in the solvent employed, varies considerably in composition and in quantity, depending upon the completeness of extracting the light-colored fraction and upon the nature and source of the starting wax product. Normally, this insoluble fraction is extremely brittle at atmospheric temperatures, frequently exhibits dull rather than shiny surfaces, is extremely dark in color, and has a high ash content. It is soluble in the usual wax solvents. It is rather heat unstable, since exposure to the air at temperatures above its melting point causes it to become increasingly viscous, with an apparent rise in its melting point.

Although the above specific procedure exhibits the use of isopropanol, any of the other solvents or combination of solvents, including those in which the wax is rendered less soluble by addition of water may be employed, the procedure being essentially the same as with the use of the isopropanol. 7

Because hard sugarcane waxes vary considerably in composition, it is necessary to determine,

, for each lot, the strength of the solvent, other than of acetone, methanol, and ethanol, which is most eifective for separating the lightfrom the dark-colored components of the wax. Acetone, methanol and ethanol are most effective in their anhydrous state. Isopropanol makes the best separation of the wax components at strengths ranging from 95% to 99%, by volume, butyl alcohol at strengths from to and ethyl acetate at strengths from 90% to with water being used as the dilutent in each case.

Having thus described the invention, what is claimed is:

1. A process of obtaining a light-colored wax product from the hard dark-colored wax product, obtained from clarification mud of sugarcane factories by extraction of a crude wax product from the mud with an organic solvent for the crude wax product and recovering the hard darkcolored wax product by distilling oflf the solvent and subjecting the residue to the action'of a selective solvent to dissolve out the fatty portions, comprising mixing the hard dark-colored wax product with a selective solvent selected from the group consisting of monohydric, saturated, aliphatic alcohols having 3 and more carbon atoms diluted with water, and acetic esters of monohydric, saturated, aliphatic alcohols diluted with water, and separating-the solution containing the light-colored wax fraction from the insoluble, very dark-colored fraction.

2. The process of claim 1, wherein the selective solvent is a monohydric, saturated, aliphatic alcohol having 3 and more carbon atoms diluted with water, whereby it will not dissolve the very dark-colored fraction.

3. The process of claim 1, wherein the selective solvent is an acetic ester of a monohydric, saturated, aliphatic alcohol diluted with water, whereby it will not dissolve the very dark-colored fraction.

CHARLES B. BROEG. ROYAL T. BALCH. 

